The YoYo Compiler is GameMaker’s high-performance export option.
UndertaleModTool has a built-in "Decompile" button, but for GMS2, it is often experimental.
UnderAnalyzer is a library-focused approach to GameMaker reverse engineering. "Written in C#, with interfaces that map to existing structures in game data", UnderAnalyzer provides both decompilation and compilation capabilities. Its features include:
As you’re looking for information on , it’s important to distinguish between the two primary ways GMS2 games are compiled, as this determines which tools—and which legal or ethical considerations—come into play. There are two main types of decompiler contexts for GMS2:
It maps out how rooms are structured, where objects are placed, and how instances interact with one another. gamemaker studio 2 decompiler
Creating a decompiler for GameMaker Studio 2 (GMS2) games involves understanding the compilation process of GMS2 and how its game files are structured. GameMaker Studio 2 uses a proprietary format for its compiled game files, which are not easily readable or editable directly. A decompiler would need to reverse-engineer this process to translate machine code or bytecode back into a form of GML (GameMaker Language) or a similar high-level representation.
Using a GameMaker Studio 2 decompiler raises several implications and ethics concerns:
The most prominent tool in this ecosystem is . Despite its name, UTMT is a fully-featured open-source data editor and decompiler for almost any modern GameMaker Studio 2 game. Core Capabilities of GMS2 Decompilers
If you must use VM, or want extra security on top of YYC, use a GML obfuscator. These tools scramble your variable, script, and object names into random strings of characters (e.g., changing scr_player_health to _a7x9 ). The game still runs perfectly, but the decompiled code becomes unreadable to humans. Encrypt External Data Files "Written in C#, with interfaces that map to
As of mid‑2020s, there is no fully reliable, public GMS2 decompiler that restores original variable names, comments, or exact project structure, especially for YYC-compiled games.
Despite its name, is the definitive open-source decompiler and editor for virtually any GameMaker Studio 2 game compiled using the VM export.
A decompiler attempts to reverse this process, taking the compiled game and generating a version of the source code that a human can read and modify. This is fundamentally different from disassembly, which produces low-level code that's still difficult for humans to understand. A decompiler aims to produce clean, readable code approximating the original.
While decompilers are powerful, they are not magic. A decompiled project is rarely an exact, 1:1 replica of the original source code due to the way compilation discards non-essential data. Creating a decompiler for GameMaker Studio 2 (GMS2)
Are you trying to understand how to safely?
If you want to know more about the , I can: Explain the difference between VM and YYC compilation.
Extracts raw assets like PNGs for sprites, WAV/OGG files for audio, and font files.